The cryspts of lieberkuhn secrete `,`

Options

A. Gastrin
B. Rennin
C. Cholecystokinin
D. Succus entricus

Answer

**Step-by-Step Solution:**

1. **Understanding the Crypts of Lieberkühn**:
The Crypts of Lieberkühn are glandular structures located in the small intestine, specifically between the villi. They play a crucial role in the secretion of intestinal juices.

2. **Identifying the Secretions**:
The cells within the Crypts of Lieberkühn, particularly the Paneth cells, are known to secrete various substances. One of the primary secretions is known as "succus entericus," which is the intestinal juice.

3. **Function of Succus Entericus**:
Succus entericus contains digestive enzymes, hormones, and mucus. It is essential for completing the digestion process initiated by pancreatic juices. It activates enzymes like trypsin, which is crucial for protein digestion.

4. **Evaluating the Options**:
- **Option A: Gastrin** - This is a hormone produced by G cells in the stomach and is not secreted by the Crypts of Lieberkühn.
- **Option B: Renin** - This enzyme is secreted by the juxtaglomerular cells in the kidneys, not by the Crypts of Lieberkühn.
- **Option C: Cholecystokinin** - This is a hormone that stimulates digestion of fats and proteins but is secreted by the duodenum, not by the Crypts of Lieberkühn.
- **Option D: Succus Entericus** - This is the correct answer as it is indeed secreted by the Crypts of Lieberkühn.

5. **Conclusion**:
After evaluating all the options, the correct answer is that the Crypts of Lieberkühn secrete "succus entericus."

**Final Answer**: The Crypts of Lieberkühn secrete succus entericus.

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